<PAGE 1> Exhibit 3 Commonwealth Energy System Form 8-K For Event Reported December 30, 1998 Notes to Consolidated Unaudited Pro Forma Condensed Financial Statements Balance Sheet 1. The historical consolidated financial statements of Commonwealth Energy System (the Parent) and its subsidiary companies as of September 30, 1998 have been adjusted to give effect to the transaction between affiliates of Southern Energy New England, L.L.C., (Southern), a subsidiary of Southern Company, and the System's subsidiaries Canal Electric Company (Canal), Cambridge Electric Light Company (Cambridge) and Commonwealth Electric Company (Commonwealth) that occurred on December 30, 1998. On that date, Canal, Cambridge and Commonwealth sold their non- nuclear generating assets to Southern. The pro forma financial statement adjustments are based on the book value of the assets that were sold by Canal, Cambridge and Commonwealth. The pro forma balance sheet also reflects the repayment of long and short-term debt with proceeds from the sale of these generating assets and proceeds from the planned issuance of long-term debt by Cambridge ($25 million) and Canal ($60 million). 2. A reconciliation of the cash proceeds from the sale of these assets and the subsequent financing plans reflected in these financial statements is as follows: (Dollars in thousands) Cash balance at September 30, 1998 $ 3,650 Proceeds from sale 461,898 Long-term debt issues 85,000 Tax liability related to sale (148,137) Transaction costs (23,223) Retirement of debt - Short-term (89,568) Long-term (93,918) Other items 6,688 Pro forma cash balance at September 30, 1998 $202,390 Income Statement The net after-tax gain from the sale of Canal Units 1 and 2 is offset on a consolidated basis by a loss recorded by the Parent for its liability to customers of Commonwealth and Cambridge pursuant to the system's divestiture filing approved by the DTE. The net after-tax gain from the sale of Cambridge's Kendall Station facilities is reflected as a regulatory liability to Cambridge's customers pursuant to the divestiture filing. <PAGE 2> Exhibit 3 (Continued) Commonwealth Energy System The pro forma income statement adjustments for electricity purchased for resale, transmission and fuel and other operation and maintenance represent the amounts resulting from the assets sold. Other operation and maintenance for the twelve months ended December 31, 1997 includes a one-time charge of $17.7 million for costs associated with a personnel reduction program implemented during the second quarter of 1997. Summary of Significant Pro Forma Adjustments Debit Credit (Dollars in thousands) Entry 1: Cash $461,898 Accumulated provision for depreciation 173,435 Property, plant and equipment $252,509 Stranded investment customer liability 396,435 Deferred tax reserve 156,638 Accrued income taxes 148,136 Provision for deferred taxes 3,298 Miscellaneous expense 8,407 To record the sale of the assets, the regulatory liability that represents the net proceeds from the sale pursuant to the system's divestiture filing with the DTE, and the accrual of income taxes associated with the sale. Entry 2: ITC Reserve 2,451 Amortization of ITC 2,451 Deferred tax reserve 2,658 Provision for deferred taxes 2,658 To reverse excess taxes and ITC relating to generating assets that were sold. Entry 3: Accrued income taxes $148,136 Transaction costs 23,223 Cash $171,359 To record the payment of income taxes and transaction costs associated with sale. <PAGE 3> Exhibit 3 (Continued) Commonwealth Energy System Entry 4: Stranded investment customer liability $31,775 Deferred charges $31,775 To record a reduction in the regulatory liability to customers for transaction costs and certain revenue. Entry 5: Cash $85,000 Long-term debt $85,000 To record the issuance of long-term debt. Entry 6: Short-term notes payable $89,568 Long-term debt 93,918 Cash $183,486 To record the retirement of long and short-term debt. Entry 7: Accounts Payable $14,085 Accounts Receivable $14,085 To reduce accounts payable and accounts receivable to reflect a more appropriate level for continuing operations.